This invention relates to heat exchangers of the type for exchanging heat primarily between two streams of fluids that are gaseous, and wherein the heat exchanger elements rotate to enhance heat transfer.
There have been various types of gas-to-gas heat exchangers in the past, where large surface areas have been provided for both fluids to effect necessary heat transfer. These heat exchangers are costly, due to the low heat transfer coefficients that gaseous fluids have, especially where the gas density is relatively low; also, such heat exchangers require a large volume to contain the necessary surface areas.